DENVER—Everyone from the Denver Broncos to the Grand Junction High School Tigers, from the Van’s Warped Tour to the Lakewood High School band have played at Invesco Field at Mile High.

Now Barack Obama will accept the Democratic nomination there, delivering a speech to as many as 76,000 people on Aug. 28, the last day of the Democratic National Convention.

Democratic National Committee Chairman Howard Dean announced the switch to the cavernous, open-air stadium on Monday. The rest of the convention, which starts Aug. 25, will be held at the Pepsi Center, which accommodates 21,000.

“Sen. Obama does not look at this as his convention, he looks at it as America’s convention,” Dean said.

Party officials said “community” credentials would be available for the public but didn’t say how many.

Obama isn’t the first Democratic presidential candidate to deliver an open-air acceptance speech. John F. Kennedy did it on July 15, 1960, at the Los Angeles Memorial Coliseum.

About 90,000 of the coliseum’s 100,000 seats were set aside for the public, news accounts said at the time.

Party officials declined to say how much it will cost them to rent the stadium. The stadium managers’ office was closed Monday and they did not return a call.

Colorado Republican State Chairman Dick Wadhams ridiculed the open-air speech as stroking Obama’s “rock star ego” and questioned whether taxpayers would be left to foot the tab along with the host committee.

Dean said the host committee would be responsible for the costs, and that Obama’s campaign would help.

“We don’t expect to leave the host committee high and dry,” Dean said.

“It’s energy, and it shows that people want to hear him so much that they need more space,” he said.

Brinkley said it also shows that Obama is “trying to be the ‘Kennedy candidate,'” and embrace a generational shift, much like Kennedy did in his campaign against the older President Nixon.

The new venue means a change in the Secret Service’s security plans and a gamble on the weather.

Ron Perea, Secret Service special agent in charge in Denver, said the agency would “make modifications as needed” as it works with local law enforcement agencies, the FBI and Federal Emergency Management Agency.

He declined to discuss what security precautions the agency would take for Obama’s event, including any restrictions on airspace and traffic.

“We’re used to this type of thing,” he said, citing Pope John Paul II’s visit to Denver in 1993 and the Group of Eight summit in the city in 1997.

August weather in Denver can be rainy or sunny, said Kyle Fredin, a meteorologist from the National Weather Service in Boulder.

The monsoon season brings rain and sometimes hail from mid-July to early September, Fredin said. But winds from the west or northwest during the monsoons can cut off the moisture.

“That’s probably what (Obama) wants,” Fredin said, “because late August and September here is pretty nice.”

Since Invesco Field opened in 2001, the $401-million stadium has hosted state high school band competitions and football championships, the heated college rivalry between Colorado-Colorado State and many rock concerts.

Last month, it was the site of the Vans Warped Tour music festival.

The Broncos played their first preseason game there on Aug. 25, but it was an Eagles concert that inaugurated the stadium on Aug. 11.

The 1.7-million-square-foot stadium’s fixtures include a stall for the team’s mascot, a stallion named Thunder; three locker rooms—one for the Broncos, one for the visiting team and one used during the annual Colorado-Colorado State football game and other non-NFL games—and two jail cells where unruly visitors can be held.